Not using a static front page, I have it set up to show the most recent post first then the rest in order. It worked fine up until today when I posted using the same theme. I only have 10 posts in there.... maybe if I change the theme? I tried to google the issue and there wasn't anything on the web to help. Maybe it's just an odd quirk.

For clarity, blogs are essentially a reverse chronological order publishing tool and you cannot change this order on a free hosted WordPress.com blog. Posts will be posted to your blog in accord with their date stamps at publication. WordPress by default shows posts in reverse chronological order (newest post on top). For returning visitors, this is very convenient since they can see the latest post without having to page down through page after page of hundreds of posts they have already read.

If you posts are not displaying in reverse chronological check your timezone. The default is UTC time. Change it to your own date and timezone on this page > Settings > General
You reset it to your own timezone by selecting the closest city to you in the same timezone in the drop-down menu you see there and then click "save changes".

Up until my most recent post (today) they have been showing up correctly in reverse chronological order. I posted my tenth post today and they went crazy. I do not have any sticky posts and I have selected the correct time zone. I went in and re-selected the correct time zone and it didn't change the posts at all. I do appreciate all the help, but so far it's a no-go. My most recent post is first, then it jumps to July, June then back to September as you scroll. It's very odd.